Rollup merge of rust-lang#112581 - TumoiYorozu:fix_url_encoding_of_percent_sign, r=notriddle

[rustdoc] Fix URL encoding of % sign

Fix rust-lang#112580

The % is encoded as %%, but the correct encoding is %25.

Author: matthiaskrgr

src/librustdoc/html/render/mod.rs

@@ -1940,8 +1940,6 @@ pub(crate) fn small_url_encode(s: String) -> String {
             // While the same is not true for hashes, rustdoc only needs to be
             // consistent with itself when encoding them.
             st += "+";
-        } else if b == b'%' {
-            st += "%%";
         } else {
             write!(st, "%{:02X}", b).unwrap();
         }